autouto o c a age e t onomic management for personalized...
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Autonomic Management for uto o c a age e t oPersonalized Handover Decisions
i H t Wi l N t kin Heterogeneous Wireless Networks
- PhD Thesis Defense -
Joon-Myung KangDecember 20, 2010
Di t ib t d P i & N t k M t L bDistributed Processing & Network Management Lab.Dept. of Computer Science and Engineering
POSTECH, Korea
Joon-Myung Kang, POSTECH PhD Thesis Defense 1/39
Presentation Outline Introduction
R l t d W kRelated Work
S l ti A hSolution Approach
Autonomic Personalized Handover DecisionAutonomic Personalized Handover Decision
Development of HMNToolSuiteDevelopment of HMNToolSuite
Evaluation and ResultsEvaluation and Results
Conclusions
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Conclusions
IntroductionIntroductionIntroductionIntroduction
1. Heterogeneous Wireless Networks2. Research Motivation3. Problem Definition4. Research Goal
Joon-Myung Kang, POSTECH PhD Thesis Defense 3/39
Heterogeneous Wireless Networks
The
ISP
TheInternet
Satellite,DVB-S, DMB-S
IP backbone관계 ID가 rId9인이미지부분을파일에서 찾을수 없습니다
관계 ID가 rId14인이미지부분을파일에서찾을수 없습니다
관계 ID가 rId17인 이미지 부분을 파일에서 찾을 수없습니다
관계 ID가 rId18인 이미지 부분을 파일에서 찾을 수 없습니다
CDMA, GSM GPRS
BroadcastNetworks
(DVB-T, DMB-T)WiBro(Mobile WiMAX)HSDPAIP-based
micro-mobility
Bluetooth Zigbee4G
DMBCamera
micro mobility
Wireless LANs
access operator
f t
DMB
MP3M-bankingIntelligent Intelligent Handover Handover DecisionDecisionIntelligent Intelligent Handover Handover DecisionDecision
HorizontalHandover
VerticalHandover
ISPASP
manufacturerPhone
NavigationSignal strength enough?Intelligent Intelligent Handover Handover DecisionDecisionIntelligent Intelligent Handover Handover DecisionDecision
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Why Personalized Decisions?User Profile
PreferenceContextContextContextContext
1
Preference Context
1
23
453 5
6Voice call
StreamingCDMA
WLANStreaming
FTPWLAN
WiBro
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WiBro
Research Motivation End users want to use mobile services simply,
conveniently, and with high quality based on their f ith t id i h down preferences without considering handover
(supporting Always-Best-Connected (ABC)) in the given environmentgiven environment
Common end users do not have much knowledge about access network technologies and mobileabout access network technologies and mobile services
Most end users do not want to be disturbed by yhandover decisions when they are using mobile services.
Autonomic and Personalized Hando er Decisions
Joon-Myung Kang, POSTECH PhD Thesis Defense 6/39
Handover Decisions
Problem DefinitionCurrent solutions lack
Personalized handover decision, where the goal is to best satisf the end ser’s needssatisfy the end-user’s needsFlexibility for accommodating horizontal and vertical handovershandoversMove from ABC to ABS (Always Best Satisfying) to CABS (Context-aware ABS)
Current solutions could benefit fromAn autonomic management architecture to govern g ghandover decisionsAn information model to enable different data to be
bi d t k i t lli t h d d i icombined to make intelligent handover decisionsConsidering multiple service requirements for handover decisions
Joon-Myung Kang, POSTECH PhD Thesis Defense 7/39
decisions
Research GoalWe propose a novel autonomic handover
decision method (AUHO) for satisfying the end user’s demand (personalization) for differentuser s demand (personalization) for different types of services in heterogeneous wireless networks
Our proposed method supports Context-aware Always Best Satisfying (CABS) handoverAlways-Best-Satisfying (CABS) handover decision as well as ABC (Always-Best-Connected) by focusing on functional and non-) y gfunctional requirements
We develop a network simulator for easily testing the quality and validity of L7 handover decision algorithms
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decision algorithms
R l t d W kR l t d W kRelated WorkRelated Work
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Related WorkDecision Function
Handover UC t t Decision
ManagementUser-
centricityContext-
awareness g
Multiple-Attribute Decisions
AI-based Approaches
Joon-Myung Kang, POSTECH PhD Thesis Defense 10/39
Comparison with Previous WorkHandover Traditional AUHOHandover Decision
Traditional(RSS-based) DF UC MAD AI CA
Multi-criteria No Yes Yes Yes Yes (FL)No (NN)
Yes
AUHO(Proposed)
Yes
Userconsideration
No Low High Medium Medium High
Efficiency Low Medium Medium High High High
High
High
Flexibility Low High High High Medium High
Implementation complexity
Low Low Low Medium High Medium
High
Highon complexity
Service type supported
Non-real-time
Non-real-time and real-time
Non-real-time
Non-real-time and real-time
Non-real-time and real-time
Non-real-time and real-time
Multiple types of services
Personalization
No No Yes No No No
Feedback control loop
No No No No No Yes
Yes
Yescontrol loop
Objective FR FR NFR FR FR FR
DF: decision function, UC: user-centric, MAD: multiple attribute decision, AI AI b d h CA t t
FR & NFR
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AI: AI-based approach, CA: context-aware, AUHO: autonomic handover decision
FR: Functional Requirements, NFR: Non-Functional Requirements
S l ti A hS l ti A hSolution ApproachSolution Approach1. Research Hypothesisesea c ypo es s2. Assumptions3. Methodologygy4. Conceptual Approach5. Context for Handover Decisions
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Research Hypothesis
Our AUHO method always“ Our AUHO method always maximizes end user satisfactionf h d d i i f diff tof handover decisions for different
types of mobile services in ypheterogeneous wireless networks
””Joon-Myung Kang, POSTECH PhD Thesis Defense 13/39
AssumptionsMobile device
Multiple active network-enabled applications Multiple network interfaces for connecting to multiple available access networks and access
i tpointsNetwork
We can use any mobile service, regardless of specific network operators or service providersNetwork operator will charge data used in transferring for handover decisions
UUserUsers can set their preferences by setting policies
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MethodologyExtend DEN-ng for representing knowledge for
handover decisionsDefine how to measure and evaluate end user
satisfactionU f l i t ll il blUse a fuzzy logic to process all available
context information which has different types of valuesof values
Use utility function to calculate satisfaction value for each access networkvalue for each access network
Define an adaptive feedback control loop for autonomic managementautonomic management
Develop a network simulator for testing efficiency of the proposed handover decision
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efficiency of the proposed handover decision
Conceptual Approach
ContextServer
OSS
OSSOSS
Mobile Device
OSS
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Mobile DeviceOSS
Heterogeneous Wireless Networks
Context for Handover Decisions
User Preference(RSS, Quality, Cost, Lifetime)
Network location, capability, service
Price charging model
CONTEXT
INFORMATION
Static
Application requirementsDevice Status Network status
Network traffic load
INFORMATION
Device StatusVelocity
Network traffic load
Dynamic
Network SideMobile Device
Dynamic
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Network SideMobile Device
Autonomic PersonalizedAutonomic PersonalizedHando er Decision Hando er Decision Handover Decision Handover Decision
ManagementManagementManagementManagement
1. Policy Definition2 Proposed AUHO algorithm2. Proposed AUHO algorithm
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Policy for Handover Decision Notation of User Profile (UP)
UP = (WR,WQ,WC,WL) Notation of Policy (P) Notation of Policy (P)
P = (Event, Condition, Action) Example of Pp
Event=VoIP• WHEN service starts, IF location=home, THEN UP=(0.40,0.40,0.1,0.1)
Event=VoIP• WHEN service starts, IF location=office, THEN UP=(0.7,0.1,0.1,0.1)
Although we use the same service, user preference can be different by the current context such as location.y
Metrics for evaluating each user preferenceCost: different cost modelQuality: Bandwidth, Delay, Jitter, BER, Throughput, Burst err, Packet Loss Ratio (PLR)Lifetime: Tx, Rx, Idle power consumption of NIC
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Proposed Algorithm (1/3) Input
Network interface list, current applicationOutputOutput
The best satisfying network interface and the best satisfying AP
Evaluation MetricsAP Acceptance Value (APAV) represents suitability of a particular AP for an end user based on a given set of user p gpreferences (e.g., RSS, Quality, Cost, and Lifetime) [0.0 ~ 1.0]AP Satisfaction Value (APSV) represents how well aAP Satisfaction Value (APSV) represents how well a particular AP satisfies the needs of the end user based on his or her user profile. We can calculate based on APAVs [0.0 ~ 1.0][ ]
GoalMaximize End User Satisfaction (APSV)
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Proposed Algorithm (2/3)START Feedback Loop
(context changes)APAV (AP Acceptance Value)APSV (AP Satisfaction Value)
START
Start an application
New AP ==Old AP
YESStart a network selection task
Wait for timeout
Maintenance LoopMaintenance Loop
Get candidate APs Apply a speed filter
Old AP
Do handoverNOStop a network selection task
Current connected AP
NO YES
Apply a SLA filterLoad current policy
Do handover
A li ti NO
Calculate APAV for the current AP
Policy?Calculate APAVs
ApplicationEnd?
YESYES
NOCalculate APSV for
the current AP
Load default policyCalculate APSVs
Select the most
Stop network selection task
NOAPSV
< δ NO
YES
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satisfying AP END
Proposed Algorithm (3/3)
Fuzzy LogicjiAP,
CONTEXT APAVFuzzy Logic
HSDPA
)()(
,
,
jiCost
jiRSS
APAPAVAPAPAV
measure of relative satisfaction
WLAN WiBro
HSDPA
CDMA
)()(
,
,
jiLifetime
jiQuality
APAPAVAPAPAV
userprofile
UtilityFunction
profile Function),( xwU
T
LifetimeQualityCostRSS wwww ,,,
APSV)
)()(
()(
)()(
,
,
,,
jiCost
jiRSS
T
jiji
APAPAVAPAPAV
wwww
APAPAVUPAPAPSV
Joon-Myung Kang, POSTECH PhD Thesis Defense 22/39
)
)()(
()(
,
,
jiLifetime
jiQualityLifetimeQualityCostRSS
APAPAVAPAPAV
wwww
Development ofDevelopment ofDevelopment ofDevelopment ofHMNToolSuiteHMNToolSuiteHMNToolSuiteHMNToolSuite
Joon-Myung Kang, POSTECH PhD Thesis Defense 23/39
HMNToolSuite Emulation and Simulation System for Heterogeneous
Mobile NetworksOpen source available at http://code.google.com/p/hmntoolsuiteCollaboration with Prof. Don Batory at UT@Austin (2008-2009)
Main FeaturesHeterogeneous mobile network map creator and emulator
• Create/modify/export network maps• Add/modify/delete wireless access networks and mobile nodes• Create new mobile nodes based on feature models• Create/modify/open/save simulation scenarios• Create/modify/delete handover decision policies for mobile nodes
H t bil t k i l tHeterogeneous mobile network simulator• Open a network map (created by the network map creator)• Visualize the path taken by mobile nodes• Support the simulation of key operational characteristics of networks• Support the simulation of key operational characteristics of networks
defined in the network map• Support the simulation of detecting available networks• Support CLI-based simulation
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HMNToolSuite
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Evaluations andEvaluations andResultsResults
1. Experimental Setup2. Results2. Results
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Experimental Setup (1/3)Hypothesis
Our AUHO method always maximizes end user satisfaction of handover decisions for differentsatisfaction of handover decisions for different types of mobile services in heterogeneous wireless networks
MethodCompare our AUHO algorithm to other standard algorithms: Random, RSS-based, Cost-based, Quality based and Lifetime basedQuality-based, and Lifetime-based
Measurement metricsMeasurement metricsQuality, cost, lifetime, end user satisfaction
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Experimental Setup (2/3)Two case studies
Same application with different user profiles• Voice call with Cost and Quality• Voice call with Quality and Lifetime
V i ll ith C t Q lit d Lif ti• Voice call with Cost, Quality, and Lifetime • Streaming …• FTP• FTP …
Different applications with a same user profile• Voice call with Cost and QualityVoice call with Cost and Quality• Streaming with Cost and Quality• FTP with Cost and Quality• Voice call with Quality and Lifetime• …
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Experimental Setup (3/3)Application ServerService1: VoIPService2: StreamingService3: FTP
Position=(147,316)Destination=(1005,520)Application: VoiceCall, Streaming, FTPNetwork Interfaces:CDMA(0:2A), WiBro(0:2B), WLAN(0:2C)
Context ServerContext: CDMA, WLAN, WiBro
Location ServerWiBro(0:2B), WLAN(0:2C)Context: location
AP1 (WLAN,11Mbps)Add 0 26
AP1 (WLAN,11Mbps)Add 0 27
(219,317)(270,326)
(344,352)
40 km/h
10 km/hBS1 (CDMA,1Mbps)Address: 0:22Pos=(226,361)
Address: 0:26Pos=(368,367)
Address: 0:27Pos=(526,396) AP3
(WLAN,11Mbps)Address: 0:36Pos=(736,451)
(610,419)
(690,451)
40 km/h
BS2 CDMA,1MbpsAddress: 0:23Pos=(491,427)
BS3
(864,504)
BS3 CDMA,1MbpsAddress: 0:32Pos=(775,502)
RAS1 WiBro,11MbpsAddress: 0:35Pos=(743,534)
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Results – Voice call & CQ (1/2)
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Results – Voice call & CQ (2/2)
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Results – Streaming & CQ (1/2)
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Results – Streaming & CQ (2/2)
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Results – summary
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ConclusionsConclusionsConclusionsConclusions
1 S1. Summary2. Contributions3 F t W k3. Future Work
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SummaryWe proposed a novel autonomic management
method for personalized handover decisions using t t i f ti li ti i t dcontext information, application requirements, and
user profiles Our AUHO determined the best satisfying AP of the Our AUHO determined the best satisfying AP of the
best satisfying access network (both horizontal and vertical handover decisions) for a programmable setvertical handover decisions) for a programmable set of user preferences and profiles
Our method outperformed other handover decision pmethods in terms of end user satisfaction
We also developed a unique and user-friendly L7 network simulation tool for testing handover decisions in heterogeneous wireless networks
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Contributions Provides an autonomic management architecture that
can deliver personalized handover decisions for heterogeneous wireless networksheterogeneous wireless networks
Provides a novel decision method by using a hybrid approach of context-aware, user-centric, multiple-attribute and fuzzy logic based approachesattribute, and fuzzy logic based approaches.
Optimizes end user satisfaction for personalized handover decisions in terms of functional and non-functional requirements
Provides seamless personalized roaming by monitoring the current context (e g location time and/or tasksthe current context (e.g., location, time, and/or tasks being performed)
Provides a network simulator for testing handover d i i l ith i h t i l t kdecision algorithms in heterogeneous wireless networks, which anyone can use for testing and comparing other handover decision algorithms
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Future WorkFuzzy logic optimization for calculating
APAVs
Optimization of weight values for buildingOptimization of weight values for building user profiles
Enhancement of our autonomic decision architecture using ontology and semanticarchitecture using ontology and semantic reasoning
More tests and optimization with considering
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handover overhead and network performance
Autonomic Management for Autonomic Management for Personalized Handover DecisionsPersonalized Handover DecisionsPersonalized Handover Decisions Personalized Handover Decisions
in Heterogeneous Wireless Networksin Heterogeneous Wireless NetworksPhD Thesis Defense, PhD Thesis Defense, JoonJoon--MyungMyung KangKang
December 20 2010December 20 2010
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December 20, 2010December 20, 2010
Publications (1/4) International Journal Papers (4)
1. Joon-Myung Kang, John Strassner, Sin-seok Seo, and James Won-KiHong, Autonomic Personalized Handover Decision for Mobile Services inHong, Autonomic Personalized Handover Decision for Mobile Services in Converged Networks, Submitted to Computer Networks, Elsevier (reviewing the first revision) (SCIE)
2 Chang-Keun Park Joon-Myung Kang JamesWon-Ki Hong Mi-Jung Choi2. Chang Keun Park, Joon Myung Kang,JamesWon Ki Hong, Mi Jung Choi, Yong-hun Lim, Seongho Ju, and Moon-suk Choi. Development and Testing of an SNMP-based Integrated Management System for Heterogeneous Power Line Communication Networks. International Journal of Network o e e Co u cat o et o s te at o a Jou a o et oManagement (IJNM), Vol. 20, Issue 1, January/February 2010, pp. 35-55. (SCIE)
3. Joon-Myung Kang, Hong-Teak Ju, Mi-Jung Choi, James Won-Ki Hong,3. Joon Myung Kang, Hong Teak Ju, Mi Jung Choi, James Won Ki Hong, and Jun-Gu Kim, OMA-DM Based Software Fault Management of Mobile Devices, International Journal of Network Management (IJNM), Vol. 19, Issue 6, November/December 2009, pp. 491-511.(SCIE), , pp ( )
4. Jae-Jo Lee, Choong Seon Hong, Joon-Myung Kang, and James Won-KiHong, Power line communication network trial and management in Korea, International Journal of Network Management (IJNM), Vol. 13, Issue 6,
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International Journal of Network Management (IJNM), Vol. 13, Issue 6, Special Issue, November/December 2006, pp. 443-457.
Publications (2/4) International Conference Papers (9) International Conference Papers (9)
1. Sin-seok Seo, Joon-Myung Kang, Nazim Agoulmine, John Strassner, James Won-Ki Hong, FAST: A Fuzzy-based Adaptive Scheduling Technique for IEEE 802.16 Networks, Accepted to appear in IM 2011
2 A K J M K Si k S S S Ki J Y Ch J h St2. Arum Kwon, Joon-Myung Kang, Sin-seok Seo, Sung-Su Kim, Jae Yoon Chung, John Strassnerand Jame Won-Ki Hong. The Design of a Quality of Experience Model for Providing High Quality Multimedia Services, The 5th IEEE International Workshop on Modelling Autonomic Communication Environments (MACE 2010) Niagara Falls, Canada, Oct. 2010, pp. 24-36.
3. Joon-Myung Kang, Chang-Keun Park, Sin-Seok Seo, Mi-Jung Choi, and Jame Won-Ki Hong. User-Centric Prediction for Battery Lifetime of Mobile Devices. 11th Asia-Pacic Network Operations and Management Symposium (APNOMS 2008), LNCS 5297, Beijing,China, Oct. 2008, pp. 531-534.
5. Joon-Myung Kang, Hong-Teak Ju, Mi-Jung Choi, and James Won-Ki Hong. OMADM Based Remote RF Signal Monitoring of Mobile Devices for QoS Improvement. 10th IFIP/IEEE International Conference on Management of Multimedia and Mobile Networks and Services (MMNS 2007), LNCS 4787, San Jose, CA, USA, Oct. 2007, pp. 76-87.( ), , , , , , pp
6. Joon-Myung Kang, Hong-Teak Ju, Mi-Jung Choi, and James Won-Ki Hong. OMA DM Based Remote Software Debugging of Mobile Devices. 10th Asia-Pacic Network Operations and Management Symposium (APNOMS 2007), LNCS 4773, Sapporo, Hokkaido, Japan, Oct. 2007, pp 51-61pp. 51 61.
7. Joon-Myung Kang, Hong-Teak Ju, and James Won-Ki Hong. Towards Autonomic Handover Decision Management in 4G Networks. 9th IFIP/IEEE International Conference on Management of Multimedia and Mobile Networks and Services (MMNS 2006), LNCS 4267, Dublin, Ireland, Oct 2006 pp 145 157
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Oct., 2006, pp. 145-157
Domestic Journal Papers (2), Domestic Conference Papers (10)
Publications (3/4)I t ti l P t t (US 3 EPO 3 J 3)International Patents (US-3, EPO-3, Japan-3)
1. Method and Apparatus for Handover decision by using Context Information in a Next-Generation Mobile Communications Network. Patent No.: 4571663, Japan 2010 08 20Japan, 2010.08.20
2. Method and Apparatus for Detecting Abnormal Battery Consumption of Mobile Devices. Patent No.:09005896.7, Europe(EPO), 2009. (Applicant: POSTECH) (Accepted to register)
3 Method for Predicting Battery Lifetime of Mobile Devices Based on Usage3. Method for Predicting Battery Lifetime of Mobile Devices Based on Usage Patterns. Patent No.: 2009-118340, Japan, 2009. (FILED)
4. Method and Apparatus for Detecting Abnormal Battery Consumption of Mobile Devices. Patent No.: , Japan, 2009. (Applicant: POSTECH) (FILED)
5 Method for Predicting Battery Lifetime of Mobile Devices Based on Usage5. Method for Predicting Battery Lifetime of Mobile Devices Based on Usage Patterns. Patent No.:12/453,141, USA, 2009. (Applicant:POSTECH) (FILED)
6. Method and Apparatus for Detecting Abnormal Battery Consumption of Mobile Devices Patent No.:12/453,142, USA, 2009. (Applicant:POSTECH) (FILED)
7 Method and Apparatus for Handover decision by using Context Information in7. Method and Apparatus for Handover decision by using Context Information in a Next-Generation Mobile Communications Network.Patent No.: 11/907,547, USA, 2007.10.15 (Applicant: POSTECH) (FILED)
8. Method for Predicting Battery Lifetime of Mobile Devices Based on Usage Patterns Patent No :09005895 9 Europe(EPO) 2009 (FILED)Patterns. Patent No.:09005895.9, Europe(EPO), 2009. (FILED)
9. Method and Apparatus for Handover decision by using Context Information in a Next-Generation Mobile Communications Network.Patent No.: 07020430.0-1249, Europe (EPO), 2007.10.18 (Applicant: POSTECH) (FILED)
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Publications (4/4) D ti P t t (7) 3 R i t d Domestic Patents (7) – 3 Registered
1. Method for Predicting Available Time Remaining on Battery in Mobile Devices Based on Usage Patterns, Patent No. 10-0981128, 2009.05.27
2 Method and Apparatus for Detecting Abnormal Power Consumption of a2. Method and Apparatus for Detecting Abnormal Power Consumption of a Battery in Mobile Devices, Patent No.:10-0969567, 2010.07.05
3. Method and Apparatus for Handover decision by using Context Information in a Next-Generation Mobile Communications Network, Patent No.: 10-0809260, 2008.02.25
4. Method for Decisioning Personalized Handover of Mobile Terminal and Mobile Terminal Performing the Same, Patent No. 10-2010-0081790, 2010.08.24 (FILED)
5. Method of Automated Answering in Mobile Communication System and5. Method of Automated Answering in Mobile Communication System and Apparatus for the Same, Patent No.: 10-2010-0081790, Korea, 2010.08.24 ( (FILED)
6. Method for Providing Autonomic Management of Software System, Recording Medium Storing Program for Performing the Same and System Having g g g y gFunction of Autonomic Management of Software, Patent No.: 10-2010-0032564, Korea, 2010.04.09 (FILED)
7. Method and Apparatus for Providing and Managing Personalized Services, Patent No.: 10-2010-0033286, Korea, 2010.04.12 (FILED)( )
Programs (11) – Registered in Korea
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Appendix IAppendix IppppHandoverHandover
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Heterogeneous Wireless NetworksDifferent access networks
WiFi, CDMA, HSDPA, WiBro, Bluetooth, etc.
Different user premisesSmart phone tablet laptop etcSmart phone, tablet, laptop, etc.
Different user demandsDifferent user demandsquality, cost, lifetime, etc.
Different service requirementsdelay, jitter, packet loss, etc.
Different environmental conditionslocation time etc
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location, time, etc.
Seamless MobilitySimple, uninterrupted access to any
type of information desired at any time,type of information desired at any time, independent of place, network, and devicedevice
Seamless handover protocole.g. IEEE 802.21 Media Independent g pHandover, Mobile IP etc.
Handover decision making algorithmE g received signal strength
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E.g. received signal strength
Handover in HWNHandover (or handoff)
Process of transferring an ongoing call or data g g gsession from one channel connected to the current network to another Horizontal
관계 ID가 rId2인 이미지 부분을 파일에서 찾을 수없습니다
H d d i i ki i HWNVertical
Handover decision making in HWNWhich access network (or access point) is the best (or
ti l)?optimal)?Received signal strength based decision (traditional)Al B t C t d (ABC)
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Always-Best-Connected (ABC)
Handover ProcessH dMobility Scenarios
HorizontalVertical
Handover Decision Criteria
RSSV l it
Handover Management
ProcessHandover Types
Hard, SoftS l
Handover Information
VelocityUser PreferencesQoS Parameters
Battery Status
Process
SeamlessFast, Smooth
EtcC
Information Gathering
Battery StatusEtc.
Handover ControlNetwork-Controlled HOMobile-Controlled HON t k A i t d HO
Handover Decision
Handover Decision Strategies
Traditional (RSS)Network-Assisted HOMobile-Assisted HO
Handover Performance
Decision Traditional (RSS)Function-based
User-CentricFuzzy Logic-based
HO LatencyPacket Loss Rate
ThroughputPi P Eff t
Handover Execution
y gNeural Network-based
Multiple AttributeContext-Aware
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Ping-Pong EffectEtc.
Hybrid
Appendix IIAppendix IIppppRelated Work DetailsRelated Work Details
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Related Work (1/5)Decision function-based strategies
[1-6][1 6]The general form of the cost function of wireless network n is [2]of wireless network n is [2]
• : the cost in the ith parameter to carry out p yservice s on network n
• : the weight (importance) assigned to using the ith parameter to perform services (with )
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Related Work (2/5)U t i t t i [7 13]User-centric strategies [7-13]
User preference (cost, QoS)p ( )Utility functionCost function example [7]Cost function example [7]
• : the time spent by the user in the ith access network
f f ( )• : : the fee per unit of time (second) that the operator of the ith access network charges to the useruser
• : the monetary cost faced by the user for a given communication session
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communication session
Related Work (3/5)Multiple attribute decision strategies
[14-18][14 18]AHP (Analytic Hierarchy Process)
• Decomposes the network selection problem into• Decomposes the network selection problem into several sub-problems and assigns a weight to each sub-problemeach sub problem
NetworkSelection
QoS Cost Lifetime
Global factors
QoS
BW d l jitt BER Tx IdleRx
Local factors
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BW delay jitter BER TxPower
Idle Power
Rx Power
Related Work (4/5)Fuzzy logic and neural networks based
strategies [19-22]strategies [19 22]
[22]
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[ ]
Related Work (5/5)Context-aware strategies [23-27]
[26]
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[ ]
Appendix IIIAppendix IIIppppContext for Handover DecisionsContext for Handover Decisions
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Context for Handover DecisionUser Metrics
User preferences (preferred cost, bandwidth rate, t k t ti it ) Q Snetwork type, power consumption , security): QoS,
Lifetime, Cost• QoS: Bandwidth Delay Jitter BER Throughput• QoS: Bandwidth, Delay, Jitter, BER, Throughput,
Burst error, Packet Loss Ratio• Lifetime: Tx, Rx, Idle Power consumption of p
network interface card• Cost: different cost model
Application MetricsBandwidth, packet error rate, delay, jitter
Service ClassesConversational, streaming, interactive, background
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Context for Handover DecisionNetwork context
Network cost, coverage, bandwidth, traffic load, jitter, supported classes of service
Link contextReceived signal strength, SNR, SIR and BER
Device capabilitiesAvailable access networks, current power level (battery level)All different network interfaces have their own characteristicsAvailable network interfaces are determined by contextAvailable network interfaces are determined by context information (location, velocity, and application)
Mobile nodeMobile nodeLocation, velocity
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Appendix IVAppendix IVppppInformation ModelingInformation Modeling
f H d D i if H d D i ifor Handover Decisionsfor Handover Decisions
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Information ModelsDEN-ng models for handover decision
Resource
PhysicalResource LogicalResource0..n 0..n0..n 0..n
PResourcesRequiredByLResources
PhysicalDevice0..n0..n Hardware0 n0 n
ConsistsOf 0..n0..nContainsHardware
PhysicalDeviceAtomic
ManagedHardwarePhysicalDeviceComposite
0..10..1{ordered}
HasDevices
0..1 0..n0..1 0..n0..10..1
MadeUpOfWirelessTechnology
MobileDevice
PhysicalPort DeviceInterface 1..n
1
1..n
SuppliesUnNumberedInterface1
0..n 0..n0..n 0..n
PPortBindsToDeviceInterfaces
MediaInterface WirelessTechnology1..n 1..n1..n 1..n
CDMATechnologyTDMATechnology FDMATechnologyCDMANetwork GSM UMTS WiMAXNetworkIEEE802_11Network
Joon-Myung Kang, POSTECH PhD Thesis Defense 59/39
Information ModelsUser Profile, Preference, Policy
PreferenceAtomic PreferenceComposite 0..10..1
0..n0..n
HasPreferences
SubscriptionPrerenceProfilePreference
DetailsECAPolicyRule0 n0 n
ManagesSubscriptionPreferences
0 n0..n 0 n0..nManagesProfilePreferences
Preference
0..n0..n
PreferencesSelectProfile0..n0..nPreferencesSelectSubscription
pDetails
0..n
0..n
0..n
0..n
ManagesPersonRoleSubscriptions0..n
0..n
0..n
0..n
ManagesPersonRoleProfiles
0..n 0..n0..n 0..n 0..n0..n 0..n0..n
ConsumerRoleSubscriptionDetails PersonRoleProfileDetails
PersonRole Profile0..n0..n 0..n0..n 0..n0..nSubscription0..n0..n
PersonRoleHasProfile...
0..n0..n
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ConsumerRole
0..n0..nConsumerRoleHasSubscription
Appendix VAppendix VppppAUHO Algorithm AUHO Algorithm PseudocodePseudocode
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Appendix VIAppendix VIppppPolicy DefinitionPolicy Definition
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Policy for Handover Decision
Example (XML)
grammargrammar
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User Profile SettingsUser profile settings mode
Ordinary user: pre-defined UpsOrdinary user: pre-defined UpsAdvanced user: manual setting mode
Examples of pre-defined UP
User RSS Cost Quality Lifetime RSS
& CCost
& Q li
Cost& Quality
RSS & Cost& Quality
preferenceRSS Cost Quality Lifetime & Cost & Quality
…
& Quality& Lifetime
& Quality& Lifetime
WRSS 0.7 0.1 0.1 0.1 0.4 0.1 0.1 0.25W 0 1 0 7 0 1 0 1 0 4 0 4 0 3 0 25WCost 0.1 0.7 0.1 0.1 0.4 0.4 0.3 0.25
WQuality 0.1 0.1 0.7 0.1 0.1 0.4 0.3 0.25WLifetime 0.1 0.1 0.1 0.7 0.1 0.1 0.3 0.25
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User Profiling User profiling is typically either knowledge- or behavior-based
The former creates static models of users and dynamically match users to the closest modelThe latter uses the user’s behavior as a model, typically using machine-learning techniques to discover useful patterns in the behavior
• Typically, this is a two-class model (e.g., like | dislike)
Knowledge must be acquired in order to create the user profileExplicit knowledge is preferred, since it can supply more detailed and useful data, but it has the drawback of interrupting the user
• Implicit knowledge acquisition is often preferred, since it has little or no impact on the user’s normal activity
• Data is discovered over a period of time; when “complete enough”, it is used to infer preferencesp
Model is then refined by monitoring subsequent behavior Typically, user profiles are organized as either
Systems that store every user’s ratings on available items so correlationSystems that store every user s ratings on available items so correlation techniques can be used to find similar users, orSystems that store representations of specific items of interest to a single user so machine-learning techniques can find similar items
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Appendix VIIAppendix VIIppppAUHO System ArchitectureAUHO System Architecture
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System Architecture
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Appendix VIIIAppendix VIIIppppAPAV Calculation DetailsAPAV Calculation Details
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APAV and APSV APAV
Suitability of a particular AP to provide services for an end user based on a given set of user preferences (e.g. RSS, Quality, Cost, and Lifetime) [0.0, 1.0]APAVs are not absolute but relative valuesIf the APAV of AP1 is greater than that of AP2 in terms of the
ifi U f AP i b h AP2 f l i h i l1 2
specific Upref, AP1 is better than AP2 for selecting the optimal APEx. If APAVQuality of AP1 is 0.7 and APAVQuality of AP2 is 0.4, AP1 is accepted for user preference Qualityaccepted for user preference Quality
APSVHow well a particular AP satisfies the needs of the en d user based on his or her user profileAPSVs are not absolute but relative valuesIf the APSV of AP2 is greater than that of AP2 in terms of an user’s UP, AP1 is preferred than AP2 (higher user satisfaction)
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Fuzzy LogicFuzzy logic:
A way to represent variation or imprecision in logicA way to make use of natural language in logicApproximate reasoning
fHumans say things like "If it is sunny and warm today, I will drive fast"
Linguistic variables:Temp: {freezing, cool, warm, hot}Cloud Cover: {overcast, partly cloudy, sunny}Speed: {slow, fast}
L. Zadah, “Fuzzy sets as a basis of possibility”
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Fuzzy Sets Systems, Vol. 1, pp3-28, 1978.
Mamdani Fuzzy Inference The most commonly used fuzzy inference technique is the so-called
Mamdani method.
In 1975, Professor Ebrahim Mamdani of London University built one of the first fuzzy systems to control a steam engine and boiler combination. He applied a set of fuzzy rules supplied by experienced human operatorshuman operators.
The Mamdani-style fuzzy inference process is performed in four steps:
1. Fuzzification of the input variables
2. Rule evaluation (inference)
3. Aggregation of the rule outputs (composition)
4. Defuzzification.
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Mamdani Fuzzy InferenceRule
IF temperature IS very cold THEN stop fanIF temperature IS very cold THEN stop fanIF temperature IS cold THEN turn down fanIF t t IS THEN i t i l lIF temperature IS warm THEN maintain levelIF temperature IS hot THEN speed up fan
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APAV CalculationMethod
We calculate an APAV using fuzzy logic, which g y g ,provides the ability to use data values that can have a specific range of values that are resolved at runtime
Four APAVs according to User PreferencesRSS: APAVRR
Cost: APAVC
Quality: APAVQy Q
Lifetime: APAVL
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APAV CalculationAPAV of RSS: APAVR
Calculated using Received Signal strengthCalculated using Received Signal strength Indicator (RSSI)Normalize the value range from 0 to 1Normalize the value range from 0 to 1High RSSI is high APAVR
APAV of Cost: APAVAPAV of Cost: APAVC$/min, $/bytes, or a flat-rate chargeNormalize the value range from 0 to 1High cost rate is low APAVC
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g C
APAV CalculationFuzzy membership functions (Output)
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APAV CalculationAPAV of Quality: APAVQ
Define 7 input metrics and 7 input membership functions: Delay, p p p yJitter, Bandwidth, BER, Throughput, BurstError, PLRDefine different fuzzy rule sets for each application type because each application requires different parameters to evaluate qualityeach application requires different parameters to evaluate qualityInput fuzzy membership functions
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APAV Calculation Three different types of applications were used
Voice call, streaming multimedia, and FTP
Example of APAVQVoice call: delay and jitter are important factorsF l d fi itiFuzzy rule definition
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APAV CalculationAPAV of Lifetime: APAVL
Define 3 input metrics and 3 input membership functions: Tx, Rx, p p pIdle powerDefine different fuzzy rule sets for each application type because each application requires different parameters to measure powereach application requires different parameters to measure power consumptionInput fuzzy membership functions
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APAV Calculation Power consumption
Three different types of applications were usedVoice call, streaming multimedia, and FTP
Example of APAVLVoice call: Tx and Rx power consumption is important factorsFuzzy rule definition
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APSV CalculationDefinition
How well a particular AP satisfies the needs of the pend user based on his or her user profile [0.0, 1.0]
MethodWe calculate an APSV using utility theory, which is widely used in economics for representing the ability of goods or services to satisfy human needsUtility: a measure of relative satisfactionUtility function
),( xwU
• a set of observed product criteria• user preferences into a real number
),( xwU
wx
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• user preferences into a real numberw
APSV CalculationAdditive aggregate utility function
Aggregate multi criteria utility of an access networkgg g y
• : the vector of n criteria • : user preference (RSS, Cost, Quality, Lifetime)
iwx
• : APAV (APAVR, APAVC, APAVQ, APAVL)• : candidate AP
E d h ibl h
i
iXiu
Easy and comprehensible approachWidely used in utility theory based approaches
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APSV Calculation APAV f ll did t AP APAVs for all candidate APs
))()()()(()( ,,,,, jiLjiQjiCjiRji APAPAVAPAPAVAPAPAVAPAPAVAPAPAV
: denotes the jth access point of the ith access network
Applying a utility function for APSV (Additive
jjQjjj
jiAP ,
y g y (aggregate utility)
)()( ,,
T
jiji APAPAVUPAPAPSV
)(
)()(
()( ,
,
jiQ
jiC
jiR
LQCR APAPAVAPAPAVAPAPAV
WWWW
)()()(
)((
,,,
,
,
jiQQjiCCjiRR
jiL
jiQ
APAPAVWAPAPAVWAPAPAVW
APAPAV
OutputSelect the most satisfying AP for the current application
)( , jiLL APAPAVW
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y g ppMaximum APSV is the best satisfying AP for end user
Appendix IXAppendix IXppppHMNToolSuiteHMNToolSuite DetailsDetails
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HMNToolSuiteWhy new simulator?
Existing network simulators focus on L2 ghandover protocols, our network simulator focus on L7We focus on higher-level aspects of the handover decisions
• How to use context information• Policies to govern handover decisions
There is a need for a more flexible and user-friendly simulation toolAnyone can test handover decision making algorithms (or other algorithms) in heterogeneo s ireless net orks
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heterogeneous wireless networks
HMNToolSuite V lid ti f Si l t Validation of our Simulator
Existing network simulator HMNToolSuite
L2 handover protocol L7 handover decisionL2 handover protocol L7 handover decision
Backend simulator Frontend simulator
Network traffic, mobile node, MAC Mobility, mobile device, policy
Our HMNToolSuite is not separate to other network simulators, it can t k t ffi t f th i ti t k i l t
, , y, , p y
Detail protocol implementation Policy-based management
use network traffic traces from the existing network simulatorsWe tested the previous handover decision algorithms on the HMNToolSuite and we can trust it due to same resultsOur simulator focuses on L7 mobility We used other L2 handoverOur simulator focuses on L7 mobility. We used other L2 handover protocols from ns-2 which has well-validated protocol modelsWe used the Free Space Path Loss Model for wireless transmission media because it is the most common model where the received signal t th i t d i f t b t l f i tstrength is computed assuming a perfect obstacle free environment,
where transmission losses due to multipath fading, shadowing, etc. are ignored.It can be easily extended with different signal modeling. The current
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y g gversion of our simulator has some limitations for applying real wireless communication environments
Appendix XAppendix XppppExperiment DetailsExperiment Details
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Network Device Parameters
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Experimental Setup Location 1
Starting point Location 2 Location 2
The delay and jitter of BS1 are higher than those of BS2, and the speed of the MN1 is changed to 10 km/h
Location 3 Location 3The power consumption rate of CDMA is lower than that of WLAN
Location 4 Location 4The quality of WLAN is lower than that of CDMA. However the price of WLAN is lower than that of CDMA
Location 5 Location 5The speed of MN1 is changed to 40 km/h. WLAN is filtered by the speed filterThe quality of BS2 is higher than that of BS3The quality of BS2 is higher than that of BS3
Location 6The price of WiBro is lower than that of CDMA
Joon-Myung Kang, POSTECH PhD Thesis Defense 89/39
Experiment Result If your decision algorithm selects the different
AP compared to other previous decision l ith i th bl ?algorithms, is there any problem?
In terms of functional requirements, our proposed algorithm did not provide a good solution for handoveralgorithm did not provide a good solution for handover decisions compared to other decision algorithms.However, we focused on end user satisfaction based on both functional and non-functional requirementsWe also considered a threshold for handover overhead to overcome degradation of performanceoverhead to overcome degradation of performance.As future work, we will show that the degradation of performance is reasonable in terms of end userperformance is reasonable in terms of end user satisfaction
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Appendix XIAppendix XIppppFuture Work DetailsFuture Work Details
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Future WorkFuzzy logic optimization for calculating APAVs
We will apply an Ant Colony Optimization algorithmOptimization of weight values for building user
profilesWe will apply a genetic algorithms
Improvement of utility function for calculating APSVs
We will apply a multiplicative utility function or other utility function to overcome the limitations
Complete autonomic decision architectureWe will apply ontology and semantic reasoning to infer new data and facts that can be used to fine-tune our decision algorithms
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decision algorithms
Ant Colony OptimizationPublication
C.-F. Juang and P.-H. Chang, “Designing g g, g gfuzzy-rule-based systems using continuous ant-colony optimization,” IEEE Transactions on Fuzzy Systems, vol. 18, no. 1, pp. 138–149, Feb. 2010.Rule generation
• Generates fuzzy rules online upon receiving t i i d ttraining data
• Initial path and solution construction• New solution generation• New solution generation• Ant path construction
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Genetic AlgorithmPublications
Kalyanomoy Deb, Amrit Pratap, Sameer Agarwal, T. M i “A F t Eliti t M lti Obj ti G tiMeyarivan, “A Fast Elitist Multi-Objective Genetic Algorithm: NSGA-II,” IEEE Transactions on Evolutionary Computation, vol. 6, 2000, pp. 182-197y p , , , ppM. Alkhawlani and A. Ayesh, "Access Network Selection Based on Fuzzy Logic and Genetic Al ith " Ad i A tifi i l I t lli lAlgorithms," Advances in Artificial Intelligence, vol. 2008, pp. 1-12.Andres J Ramirez David B Knoester Betty H CAndres J. Ramirez , David B. Knoester , Betty H.C. Cheng , Philip K. McKinley, "Applying genetic algorithms to decision making in autonomic
ti t " P di f th 6thcomputing systems," Proceedings of the 6th International Conference on Autonomic Computing, June 15-19, 2009, Barcelona, Spain.
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June 15 19, 2009, Barcelona, Spain.
Utility functionAdditive utility function has some serious
limitationsWhether the multi-criteria utility function can be separated into independent parts where ui, the utility of criterion i, does not dependent on the value of other criteriaIf it i d d b t d th l t tilitIf it can indeed be separated, the elementary utility ui(xi) can simply be added to produce the aggregate utilityutilityIf they are not independent, we will apply a multiplicative utility function presented in [93]multiplicative utility function presented in [93]
[93] Q.T. Nguyen-Vuong, Y. Ghamri-Doudane, and N. Agoulmine. On utility models for access network selection in wireless h t t k I N t k O ti d M t
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heterogeneous networks. In Network Operations and Management Symposium, 2008. NOMS 2008. IEEE, pages 144-151. IEEE, 2008.
Novel Approach?Proved from our patents
5 patents (2 KR, 1 EPO, 1 JP, and 1 US)• 2 Registered (KR JP)2 Registered (KR, JP)• 1 will be registered soon (US)
Functional and Non-functional requirementsDiff t l ti th d li ti tDifferent evaluation method as application typesEnd user satisfaction based on user preference
and profileand profileDecision for both horizontal and vertical handoverScalability and flexibilityy y L7 handover decisionEasy to generalize due to technology-neutral
approachesapproaches
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Integration with Real SystemAssumptions
Difficult to deploy the unified OSS (OperationsDifficult to deploy the unified OSS (Operations Supported System) to gather all available context information due to the federationcontext information due to the federation problems in network operators and service providersproviders.
SolutionHowever, if these problems will be solved, our approach will be directly applied to handover decisions for personalized services.
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Practical AspectOur approach can apply the current
mobile device in heterogeneous wireless networks operated by one network operators (KT, SKT or LGT)
In the future, if the federation problem will be solved among network operators, our approach is easy to apply
Handover overhead is a big problem, but g p ,L2 handover should be optimized for reducing overheadg
We have discussed with engineers from KT, SKT, LGT, and Samsung
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, S , G , a d Sa su g